[Interpreter] Remove register file register and replace with LoadParentFramePointer.

src/mips/builtins-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_MIPS
 
 #include "src/codegen.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 1021 matching lines @@
     // TODO(rmcilroy): Consider doing more than one push per loop iteration.
     __ push(t1);
     // Continue loop if not done.
     __ bind(&loop_check);
     __ Subu(t0, t0, Operand(kPointerSize));
     __ Branch(&loop_header, ge, t0, Operand(zero_reg));
   }
 
   // Load bytecode offset and dispatch table into registers.
   __ LoadRoot(kInterpreterAccumulatorRegister, Heap::kUndefinedValueRootIndex);
-  __ Addu(kInterpreterRegisterFileRegister, fp,
-          Operand(InterpreterFrameConstants::kRegisterFilePointerFromFp));
+  __ Addu(t3, fp, Operand(InterpreterFrameConstants::kRegisterFileFromFp));
   __ li(kInterpreterBytecodeOffsetRegister,
         Operand(BytecodeArray::kHeaderSize - kHeapObjectTag));
   __ li(kInterpreterDispatchTableRegister,
         Operand(ExternalReference::interpreter_dispatch_table_address(
             masm->isolate())));
 
   // Dispatch to the first bytecode handler for the function.
   __ Addu(a0, kInterpreterBytecodeArrayRegister,
           kInterpreterBytecodeOffsetRegister);
   __ lbu(a0, MemOperand(a0));
   __ Lsa(at, kInterpreterDispatchTableRegister, a0, kPointerSizeLog2);
   __ lw(at, MemOperand(at));
   __ Call(at);
 
   // Even though the first bytecode handler was called, we will never return.
   __ Abort(kUnexpectedReturnFromBytecodeHandler);
 
   // Load debug copy of the bytecode array.
   __ bind(&load_debug_bytecode_array);
   __ lw(kInterpreterBytecodeArrayRegister,
         FieldMemOperand(debug_info, DebugInfo::kAbstractCodeIndex));
   __ Branch(&bytecode_array_loaded);
 }
 
 
 void Builtins::Generate_InterpreterExitTrampoline(MacroAssembler* masm) {
-  // TODO(rmcilroy): List of things not currently dealt with here but done in
-  // fullcodegen's EmitReturnSequence.
-  //  - Supporting FLAG_trace for Runtime::TraceExit.
-  //  - Support profiler (specifically decrementing profiling_counter
-  //    appropriately and calling out to HandleInterrupts if necessary).
-
   // The return value is in accumulator, which is already in v0.
 
   // Leave the frame (also dropping the register file).
   __ LeaveFrame(StackFrame::JAVA_SCRIPT);
 
   // Drop receiver + arguments and return.
   __ lw(at, FieldMemOperand(kInterpreterBytecodeArrayRegister,
                             BytecodeArray::kParameterSizeOffset));
   __ Addu(sp, sp, at);
   __ Jump(ra);
@@ skipping 58 matching lines @@
   __ push(t1);
   __ bind(&loop_check);
   __ Branch(&loop_header, gt, a2, Operand(t0));
 
   // Call the constructor with a0, a1, and a3 unmodified.
   __ Jump(masm->isolate()->builtins()->Construct(), RelocInfo::CODE_TARGET);
 }
 
 
 static void Generate_EnterBytecodeDispatch(MacroAssembler* masm) {
-  // Initialize register file register and dispatch table register.
-  __ Addu(kInterpreterRegisterFileRegister, fp,
-          Operand(InterpreterFrameConstants::kRegisterFilePointerFromFp));
+  // Initialize the dispatch table register.
   __ li(kInterpreterDispatchTableRegister,
         Operand(ExternalReference::interpreter_dispatch_table_address(
             masm->isolate())));
 
   // Get the bytecode array pointer from the frame.
-  __ lw(
-      kInterpreterBytecodeArrayRegister,
-      MemOperand(kInterpreterRegisterFileRegister,
-                 InterpreterFrameConstants::kBytecodeArrayFromRegisterPointer));
+  __ lw(kInterpreterBytecodeArrayRegister,
+        MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
 
   if (FLAG_debug_code) {
     // Check function data field is actually a BytecodeArray object.
     __ SmiTst(kInterpreterBytecodeArrayRegister, at);
     __ Assert(ne, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry, at,
               Operand(zero_reg));
     __ GetObjectType(kInterpreterBytecodeArrayRegister, a1, a1);
     __ Assert(eq, kFunctionDataShouldBeBytecodeArrayOnInterpreterEntry, a1,
               Operand(BYTECODE_ARRAY_TYPE));
   }
 
   // Get the target bytecode offset from the frame.
   __ lw(kInterpreterBytecodeOffsetRegister,
-        MemOperand(
-            kInterpreterRegisterFileRegister,
-            InterpreterFrameConstants::kBytecodeOffsetFromRegisterPointer));
+        MemOperand(fp, InterpreterFrameConstants::kBytecodeOffsetFromFp));
   __ SmiUntag(kInterpreterBytecodeOffsetRegister);
 
   // Dispatch to the target bytecode.
   __ Addu(a1, kInterpreterBytecodeArrayRegister,
           kInterpreterBytecodeOffsetRegister);
   __ lbu(a1, MemOperand(a1));
   __ Lsa(a1, kInterpreterDispatchTableRegister, a1, kPointerSizeLog2);
   __ lw(a1, MemOperand(a1));
   __ Jump(a1);
 }
@@ skipping 1678 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS